The present invention generally relates to spreaders and more particularly, to an improved spreader which uses a transmission drive assembly.
Conventional spreaders employ a spinner drive assembly which is mounted within the hopper. The hopper receives and stores, for example, salt or other materials to be spread. The drive assembly includes a drive housing and motor assembly mounted inside the hopper. The motor assembly includes a motor, two drive pulleys connected by a drive belt, and a bearing assembly. Mounted to one of the pulleys and journaled within the bearing assembly is a drive shaft which has an auger attached adjacent the free end of the shaft. All of these elements are mounted within the hopper and typically are surrounded by salt. To reduce corrosion of the assembly, a motor cap is mounted over the motor assembly.
The shaft typically extends out of the base of the hopper and a spinner is mounted to the shaft. The free end of the shaft is journaled within a second bearing mounted to a H-frame assembly. In operation, salt is placed in the hopper and the auger pulls salt through the bottom opening in the hopper where it contacts the spinner and is thrown out over a predetermined radius.
These types of spreaders experience several problems. First, since the motor assembly is mounted inside of the hopper, it is susceptible to corrosion. The motor typically is surrounded by highly corrosive salt which tends to corrode the motor assembly. Additionally, the shaft has to be fairly long in order to extend from the motor assembly through the H-frame and be mounted within the bearing. As a result of the length of the shaft, the bearings experience a large amount of stress and are highly susceptible to failure. Further, the ability to repair the system is difficult because the motor assembly is mounted within the housing and must be removed for repair. Any belts which need to be replaced must be replaced within the hopper or the motor assembly must be removed. A still further problem is corrosion of the shaft since that shaft is always within the salt or other material held within the hopper. A further problem with these types of systems is the inability to lubricate the bearings, particularly the bearing which is mounted in the hopper. Without proper lubrication, these bearings fail and must be replaced. Because of the difficulty in lubricating the bearings, the bearings experience a high failure rate.
Another disadvantage of known spreaders is the need for a large motor to drive the auger and spinner. These motors are heavy, expensive and do not experience long operational lives.
A still further problem with conventional spreader assemblies is the time required to install them on a vehicle and the damage done to the vehicle when the units are installed. Common spreader frame structures are difficult to install. The various components of the frame structure have to be properly positioned and then holes drilled into the truck bed or rails and bumper. Several hours are required for a typical assembly. Additionally, the spreader support frames are designed for a particular vehicle which creates the need for large inventories of frames to fit various vehicles.
Other problems with swing-away spreaders is the damage that can be done to the spreader assembly and the vehicle when a loaded spreader is pivoted. As will be appreciated, with a hopper full of salt, the weight in the pivoted position is supported only by the pivot rod which can result in the pivot rod the bumper or the support frame being bent. Another problem with all known spreaders is that the hopper top has a tendency to blow off due to air blowing over the vehicle.